Panthera Leo Atrox, also known as the American Lion, is an extinct lion of the family Felidae, endemic to North America and northwestern South America during the Pleistocene epoch (0.34 mya to 11,000 years ago), existing for approximately 0.33 million years. In the episode "Ice Age Monsters", a bald male lion killed a steppe bison before Arctodus, the short-faced bear, arrives. Arctodus was swiped right on the face and this gives the chance for the American Lion to bite the bear's throat, but the lion was thrown into a huge hole and dies from the fall.